1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Operations on the network namespace
5 #ifndef __NET_NET_NAMESPACE_H
6 #define __NET_NET_NAMESPACE_H
8 #include <linux/atomic.h>
9 #include <linux/refcount.h>
10 #include <linux/workqueue.h>
11 #include <linux/list.h>
12 #include <linux/sysctl.h>
13 #include <linux/uidgid.h>
16 #include <net/netns/core.h>
17 #include <net/netns/mib.h>
18 #include <net/netns/unix.h>
19 #include <net/netns/packet.h>
20 #include <net/netns/ipv4.h>
21 #include <net/netns/ipv6.h>
22 #include <net/netns/nexthop.h>
23 #include <net/netns/ieee802154_6lowpan.h>
24 #include <net/netns/sctp.h>
25 #include <net/netns/dccp.h>
26 #include <net/netns/netfilter.h>
27 #include <net/netns/x_tables.h>
28 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
29 #include <net/netns/conntrack.h>
31 #include <net/netns/nftables.h>
32 #include <net/netns/xfrm.h>
33 #include <net/netns/mpls.h>
34 #include <net/netns/can.h>
35 #include <net/netns/xdp.h>
36 #include <net/netns/bpf.h>
37 #include <linux/ns_common.h>
38 #include <linux/idr.h>
39 #include <linux/skbuff.h>
40 #include <linux/notifier.h>
42 struct user_namespace;
43 struct proc_dir_entry;
46 struct ctl_table_header;
53 #define NETDEV_HASHBITS 8
54 #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS)
57 /* First cache line can be often dirtied.
58 * Do not place here read-mostly fields.
60 refcount_t passive; /* To decide when the network
61 * namespace should be freed.
63 spinlock_t rules_mod_lock;
65 unsigned int dev_unreg_count;
67 unsigned int dev_base_seq; /* protected by rtnl_mutex */
73 struct list_head list; /* list of network namespaces */
74 struct list_head exit_list; /* To linked to call pernet exit
75 * methods on dead net (
76 * pernet_ops_rwsem read locked),
77 * or to unregister pernet ops
78 * (pernet_ops_rwsem write locked).
80 struct llist_node cleanup_list; /* namespaces on death row */
83 struct key_tag *key_domain; /* Key domain of operation tag */
85 struct user_namespace *user_ns; /* Owning user namespace */
86 struct ucounts *ucounts;
91 struct list_head dev_base_head;
92 struct proc_dir_entry *proc_net;
93 struct proc_dir_entry *proc_net_stat;
96 struct ctl_table_set sysctls;
99 struct sock *rtnl; /* rtnetlink socket */
100 struct sock *genl_sock;
102 struct uevent_sock *uevent_sock; /* uevent socket */
104 struct hlist_head *dev_name_head;
105 struct hlist_head *dev_index_head;
106 struct raw_notifier_head netdev_chain;
108 /* Note that @hash_mix can be read millions times per second,
109 * it is critical that it is on a read_mostly cache line.
113 struct net_device *loopback_dev; /* The loopback */
116 struct list_head rules_ops;
118 struct netns_core core;
119 struct netns_mib mib;
120 struct netns_packet packet;
121 struct netns_unix unx;
122 struct netns_nexthop nexthop;
123 struct netns_ipv4 ipv4;
124 #if IS_ENABLED(CONFIG_IPV6)
125 struct netns_ipv6 ipv6;
127 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
128 struct netns_ieee802154_lowpan ieee802154_lowpan;
130 #if defined(CONFIG_IP_SCTP) || defined(CONFIG_IP_SCTP_MODULE)
131 struct netns_sctp sctp;
133 #if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
134 struct netns_dccp dccp;
136 #ifdef CONFIG_NETFILTER
139 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
142 #if defined(CONFIG_NF_TABLES) || defined(CONFIG_NF_TABLES_MODULE)
143 struct netns_nftables nft;
145 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
146 struct netns_nf_frag nf_frag;
147 struct ctl_table_header *nf_frag_frags_hdr;
150 struct sock *nfnl_stash;
151 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
152 struct list_head nfct_timeout_list;
155 #ifdef CONFIG_WEXT_CORE
156 struct sk_buff_head wext_nlevents;
158 struct net_generic __rcu *gen;
160 /* Used to store attached BPF programs */
161 struct netns_bpf bpf;
163 /* Note : following structs are cache line aligned */
165 struct netns_xfrm xfrm;
168 atomic64_t net_cookie; /* written once */
170 #if IS_ENABLED(CONFIG_IP_VS)
171 struct netns_ipvs *ipvs;
173 #if IS_ENABLED(CONFIG_MPLS)
174 struct netns_mpls mpls;
176 #if IS_ENABLED(CONFIG_CAN)
177 struct netns_can can;
179 #ifdef CONFIG_XDP_SOCKETS
180 struct netns_xdp xdp;
182 #if IS_ENABLED(CONFIG_CRYPTO_USER)
183 struct sock *crypto_nlsk;
185 struct sock *diag_nlsk;
186 } __randomize_layout;
188 #include <linux/seq_file_net.h>
190 /* Init's network namespace */
191 extern struct net init_net;
194 struct net *copy_net_ns(unsigned long flags, struct user_namespace *user_ns,
195 struct net *old_net);
197 void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid);
199 void net_ns_barrier(void);
200 #else /* CONFIG_NET_NS */
201 #include <linux/sched.h>
202 #include <linux/nsproxy.h>
203 static inline struct net *copy_net_ns(unsigned long flags,
204 struct user_namespace *user_ns, struct net *old_net)
206 if (flags & CLONE_NEWNET)
207 return ERR_PTR(-EINVAL);
211 static inline void net_ns_get_ownership(const struct net *net,
212 kuid_t *uid, kgid_t *gid)
214 *uid = GLOBAL_ROOT_UID;
215 *gid = GLOBAL_ROOT_GID;
218 static inline void net_ns_barrier(void) {}
219 #endif /* CONFIG_NET_NS */
222 extern struct list_head net_namespace_list;
224 struct net *get_net_ns_by_pid(pid_t pid);
225 struct net *get_net_ns_by_fd(int fd);
227 u64 __net_gen_cookie(struct net *net);
230 void ipx_register_sysctl(void);
231 void ipx_unregister_sysctl(void);
233 #define ipx_register_sysctl()
234 #define ipx_unregister_sysctl()
238 void __put_net(struct net *net);
240 static inline struct net *get_net(struct net *net)
242 refcount_inc(&net->ns.count);
246 static inline struct net *maybe_get_net(struct net *net)
248 /* Used when we know struct net exists but we
249 * aren't guaranteed a previous reference count
250 * exists. If the reference count is zero this
251 * function fails and returns NULL.
253 if (!refcount_inc_not_zero(&net->ns.count))
258 static inline void put_net(struct net *net)
260 if (refcount_dec_and_test(&net->ns.count))
265 int net_eq(const struct net *net1, const struct net *net2)
270 static inline int check_net(const struct net *net)
272 return refcount_read(&net->ns.count) != 0;
275 void net_drop_ns(void *);
279 static inline struct net *get_net(struct net *net)
284 static inline void put_net(struct net *net)
288 static inline struct net *maybe_get_net(struct net *net)
294 int net_eq(const struct net *net1, const struct net *net2)
299 static inline int check_net(const struct net *net)
304 #define net_drop_ns NULL
314 static inline void write_pnet(possible_net_t *pnet, struct net *net)
321 static inline struct net *read_pnet(const possible_net_t *pnet)
330 /* Protected by net_rwsem */
331 #define for_each_net(VAR) \
332 list_for_each_entry(VAR, &net_namespace_list, list)
333 #define for_each_net_continue_reverse(VAR) \
334 list_for_each_entry_continue_reverse(VAR, &net_namespace_list, list)
335 #define for_each_net_rcu(VAR) \
336 list_for_each_entry_rcu(VAR, &net_namespace_list, list)
341 #define __net_initdata
342 #define __net_initconst
344 #define __net_init __init
345 #define __net_exit __ref
346 #define __net_initdata __initdata
347 #define __net_initconst __initconst
350 int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp);
351 int peernet2id(const struct net *net, struct net *peer);
352 bool peernet_has_id(const struct net *net, struct net *peer);
353 struct net *get_net_ns_by_id(const struct net *net, int id);
355 struct pernet_operations {
356 struct list_head list;
358 * Below methods are called without any exclusive locks.
359 * More than one net may be constructed and destructed
360 * in parallel on several cpus. Every pernet_operations
361 * have to keep in mind all other pernet_operations and
362 * to introduce a locking, if they share common resources.
364 * The only time they are called with exclusive lock is
365 * from register_pernet_subsys(), unregister_pernet_subsys()
366 * register_pernet_device() and unregister_pernet_device().
368 * Exit methods using blocking RCU primitives, such as
369 * synchronize_rcu(), should be implemented via exit_batch.
370 * Then, destruction of a group of net requires single
371 * synchronize_rcu() related to these pernet_operations,
372 * instead of separate synchronize_rcu() for every net.
373 * Please, avoid synchronize_rcu() at all, where it's possible.
375 * Note that a combination of pre_exit() and exit() can
376 * be used, since a synchronize_rcu() is guaranteed between
379 int (*init)(struct net *net);
380 void (*pre_exit)(struct net *net);
381 void (*exit)(struct net *net);
382 void (*exit_batch)(struct list_head *net_exit_list);
388 * Use these carefully. If you implement a network device and it
389 * needs per network namespace operations use device pernet operations,
390 * otherwise use pernet subsys operations.
392 * Network interfaces need to be removed from a dying netns _before_
393 * subsys notifiers can be called, as most of the network code cleanup
394 * (which is done from subsys notifiers) runs with the assumption that
395 * dev_remove_pack has been called so no new packets will arrive during
396 * and after the cleanup functions have been called. dev_remove_pack
397 * is not per namespace so instead the guarantee of no more packets
398 * arriving in a network namespace is provided by ensuring that all
399 * network devices and all sockets have left the network namespace
400 * before the cleanup methods are called.
402 * For the longest time the ipv4 icmp code was registered as a pernet
403 * device which caused kernel oops, and panics during network
404 * namespace cleanup. So please don't get this wrong.
406 int register_pernet_subsys(struct pernet_operations *);
407 void unregister_pernet_subsys(struct pernet_operations *);
408 int register_pernet_device(struct pernet_operations *);
409 void unregister_pernet_device(struct pernet_operations *);
412 struct ctl_table_header;
415 int net_sysctl_init(void);
416 struct ctl_table_header *register_net_sysctl(struct net *net, const char *path,
417 struct ctl_table *table);
418 void unregister_net_sysctl_table(struct ctl_table_header *header);
420 static inline int net_sysctl_init(void) { return 0; }
421 static inline struct ctl_table_header *register_net_sysctl(struct net *net,
422 const char *path, struct ctl_table *table)
426 static inline void unregister_net_sysctl_table(struct ctl_table_header *header)
431 static inline int rt_genid_ipv4(const struct net *net)
433 return atomic_read(&net->ipv4.rt_genid);
436 #if IS_ENABLED(CONFIG_IPV6)
437 static inline int rt_genid_ipv6(const struct net *net)
439 return atomic_read(&net->ipv6.fib6_sernum);
443 static inline void rt_genid_bump_ipv4(struct net *net)
445 atomic_inc(&net->ipv4.rt_genid);
448 extern void (*__fib6_flush_trees)(struct net *net);
449 static inline void rt_genid_bump_ipv6(struct net *net)
451 if (__fib6_flush_trees)
452 __fib6_flush_trees(net);
455 #if IS_ENABLED(CONFIG_IEEE802154_6LOWPAN)
456 static inline struct netns_ieee802154_lowpan *
457 net_ieee802154_lowpan(struct net *net)
459 return &net->ieee802154_lowpan;
463 /* For callers who don't really care about whether it's IPv4 or IPv6 */
464 static inline void rt_genid_bump_all(struct net *net)
466 rt_genid_bump_ipv4(net);
467 rt_genid_bump_ipv6(net);
470 static inline int fnhe_genid(const struct net *net)
472 return atomic_read(&net->fnhe_genid);
475 static inline void fnhe_genid_bump(struct net *net)
477 atomic_inc(&net->fnhe_genid);
480 #endif /* __NET_NET_NAMESPACE_H */